Ceramic wear tile and method of using same

ABSTRACT

The present subject matter provides colored wear tiles for use in optical sorting apparatuses and related methods that separate an associated material into a desired product and an undesired product. The colored wear tiles have a color and/or lightness value that permeates the entire body of the wear tile and sufficiently differs from the color and/or lightness of the associated material in order to allow the colored wear tile, or portions or pieces thereof, that may mix with the associated material, to be separated from the desired product by the sorting apparatus.

CROSS REFERENCE TO RELATED APPLICATION

The present application claims priority upon U.S. Provisional PatentApplication Ser. No. 61/836,781 filed Jun. 19, 2013, which isincorporated herein by reference.

FIELD

The present subject matter relates to colored wear tiles used in varioussorting devices and related methods.

BACKGROUND

Many processes are known for sorting and separating material. Theseprocesses are often mechanical in nature and performed by an automatedmachine or apparatus that is controlled by a computer. These sortingmachines, or portions thereof, can experience wear attendant to contactwith associated material during sorting operations. Often these partsare made from stainless steel and can have service lives of up to oneyear depending on thickness. Wear tiles are often applied to these steelportions of the machines that are subject to such wear in order toextend the working life of the parts and the machine as a whole. Thewear tile is used as a barrier between the associated material and themachine parts so that the wear tile itself is worn away, rather than themachine parts being worn.

The material to be sorted is normally separated into two or more groups.These groups can include for example, a group of material that isacceptable or desired for use or consumption (i.e., desired product),and a group that is not acceptable or undesired for use or consumption(i.e., undesired product).

Various characteristics or properties of the material are used as thebasis for separating the material into these groups. Parameters areestablished for sorting out undesired material from desired materialbased on the properties being monitored. Often, optical and/or physicalproperties of the material are monitored and used as the basis forseparation. In these cases, material is normally sorted with opticalscanning systems that employ cameras, lights, and sensors of variouskinds to monitor or detect certain properties of the material forexample, size, color, transparency or opacity, reflectivity, infra-redabsorption/reflectivity, combinations thereof, and the like.

If wear tiles are introduced into a sorting machine, the wear tiles, orportions thereof may chip from the wear tiles during sorting operationsand inadvertently mix with the material to be sorted. Standard weartiles used in sorting machines are various shades of white resultingfrom the material components used to form the tiles. When used inmachines using optical sorters for the separation of food products suchas white rice, for example, white wear tiles are inadequate. White weartiles do not exhibit optical properties sufficiently different from theoptical properties of the white rice—or other material with shades ofwhite—in order to allow the optical scanning system to separate chippedwhite wear tile from the desired product.

SUMMARY

The difficulties and drawbacks associated with previously known weartiles and sorting methods are overcome in the present colored wear tilesand related apparatuses and methods.

In one aspect of the present subject matter, a sorting apparatus isprovided comprising a feed, an implement, and wear tiles. The feeddelivers a material to be sorted to the implement. The implement sortsthe material into at least two groups based on one or morecharacteristics of the material including a color parameter, one of theat least two groups comprising desired product and the other of the atleast two groups comprising an undesired product. The wear tiles cover aportion of the sorting apparatus to substantially prevent the materialfrom contacting the covered portion of the sorting apparatus duringsorting. The wear tiles have a color sufficiently different from a colorof the desired product such that the wear tiles, or portions or piecesthereof, that may mix with the material are sorted by the implement fromthe desired product.

In another aspect of the present subject matter, a method is providedfor separating a material into at least two groups based oncharacteristics of the material, the characteristics including a colorparameter and a lightness parameter. The method comprises providing thematerial to be separated. The method includes providing a sortingapparatus having a feed, a sorting implement, and colored wear tiles;wherein the feed transports the material to the sorting implement, thesorting implement separates the material into at least two groups basedon the characteristics of the material, the colored wear tiles coverportions of the apparatus to substantially prevent the covered portionsfrom coming into contact with the material, and the colored wear tileshave a color and a lightness. The method also comprises passing thematerial through the sorting apparatus to separate the material into theat least two groups, one of the at least two groups comprising desiredproduct having a color and lightness, the other of the at least twogroups comprising undesired product. The sorting implement separates thecolored wear tiles, or portions or pieces thereof, that may mix with thematerial, from the desired product based on differences between thecolor and lightness of the colored wear tiles and the color andlightness of the desired product.

In another aspect of the present subject matter, an apparatus isprovided for separating portions of a material into a desired productportion and an undesired product portion, wherein the separating isbased on perceptible characteristics of the material, one of theperceptible characteristics being color. The apparatus comprises adelivery system for transporting the material to be sorted; a dividerfor separating the desired product from the undesired product, andcolored wear tiles covering portions of the apparatus that otherwisewould be subject to wear from coming into contact with the material. Thecolored wear tiles have a color that permeates substantially an entiremass of the colored wear tiles. The color of the colored wear tiles issufficiently different from the color of the material such that thedivider is able to separate the colored wear tiles, or portions orpieces thereof that may mix with the material, from the desired productportion. The delivery system transports the material to the divider, andthe divider separates the material.

In another aspect of the present subject matter, a method is providedfor protecting one or more surfaces of an optical sorting apparatus thatare subject to wear. The apparatus is configured to sort a materialbased on characteristics including color. The wear is associated withthe material contacting the one or more surfaces. The method comprisescovering the one or more surfaces with colored wear tiles so as tosubstantially prevent the material from contacting the one or moresurfaces. The material is sorted into two or more groups, one of the twoor more groups comprising desired product having a color, the other ofthe two or more groups comprising undesired product. The colored weartiles have a color that permeates substantially an entire mass of thecolored wear tiles, the color of the colored wear tiles being differentfrom the color of the desired product. The colored wear tiles, orportions or pieces thereof, that may mix with the material are separatedfrom the desired product by the apparatus on the basis of a differencebetween the color of the colored wear tiles and the color of the desiredproduct.

In another aspect of the present subject matter, a colored wear tile isprovided for inhibiting wear to a surface, the wear being associated tocontact with a moving material. The colored wear tile comprises prior tofiring, non-volatile components comprising at least 85% Al₂O₃ by weight(“wt. %”). The colored wear tile comprises prior to firing, Al₂O₃ fromat least 75 wt. % of the total weight of the volatile and non-volatilecomponents and excluding water. The colored wear tile has a color thatpermeates substantially an entire mass of the colored wear tile. Thecolored wear tile has a Vickers hardness from about 900 HV5 to about1350 HV5. The colored wear tile has a thickness of less than about 0.60inches. The colored wear tile has a lightness of about 90 or lessmeasured with a CIE D65 illuminant at 10 degrees.

The colored wear tile in accordance with the present subject matterprovides sufficient difference in color and/or lightness from thematerial to be sorted, in order to allow optical scanning machines toseparate the wear tiles, or portions thereof, from the desired product.Related apparatuses and methods employing the colored wear tile provideimproved sorting performance over the traditional use of white weartiles.

As will be realized, the present subject matter is capable of other anddifferent embodiments and its several details are capable ofmodifications in various respects, all without departing from thepresent subject matter. Accordingly, the description is to be regardedas illustrative and not restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

These, as well as other features, aspects, and advantages of the presentsubject matter, will be more completely understood and appreciated byreferring to the following more detailed description of the exemplaryembodiments of the present subject matter in conjunction with theaccompanying drawings.

FIGS. 1A-1G are schematic, perspective views of wear tiles in accordancewith the present subject matter.

FIG. 2 is a schematic, cross-sectional view of a sorting apparatusincluding colored wear tiles in accordance with the present subjectmatter.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The present subject matter provides colored wear tiles that are used inoptical sorting apparatuses and related methods for separating anassociated material into at least two groups, the two groups comprisinga desired product group and an undesired product group. The colored weartiles provide protection to portions of the optical sorting apparatusfrom wear that occurs from contact with the associated material. Thewear tile has a color characteristic and/or a lightness characteristicthat are different from the color and/or lightness characteristics ofthe associated material such that optical systems used in the sortingapparatus are able to monitor and detect these differences, wherebypieces or portions of the wear tile that may mix with the materialduring sorting operations are separated from the desired product by thesorting apparatus.

By “portions” or “pieces”, it is meant fragments or parts of the weartiles that are optically significant. By “optically significant”, it ismeant a fragment of the wear tile having a size that is large enough tobe separated from the desired product by the sorting machine. A moredetailed description of the colored wear tiles, sorting apparatuses, andmethods is provided below in reference to the figures.

Size and Shape

In accordance with the present subject matter, and in reference to FIGS.1A-1D, a colored wear tile 1 has an exposed surface 10 that comes intocontact with an associated material during sorting, a back surface 20used to attach the tile 1 to the portion of the sorting apparatussubject to wear, and one or more side surfaces 30. The tiles have a sizeand shape adapted to be mounted on portions of an optical sortingapparatus in order to prevent wear on those portions that come intocontact with associated material during sorting.

Except for having a thickness 40 of about 0.60 inches or less, the shapeor form of the “tile” is not particularly limited. Therefore, the term“tile” should not be construed as being restrictive in regard to shape,size, and proportions of the wear tile. The colored wear tile of thepresent subject matter can have any shape, size, form, or proportionsand is not limited to standard “tile” sizes such as those having athickness 40 that is significantly smaller than a length 50 and width60, such as is domestic tile applications. Rather, the present subjectmatter contemplates wear tiles that have flat surfaces (e.g. exposedsurface 10 in FIG. 1A), curved/contoured surfaces (e.g. exposed surface10 in FIG. 1D), or combinations thereof (e.g. exposed surface 10 andback surface 20 in FIG. 1D) and have a thickness 40 that is equal to,greater, or less than either or both the width 60 and length 50 of thetile 1. The tile can be a unitary, pre-formed single-piece wear memberthat lines or covers the entirety of a structure or part(s) thereof. Thetile can be in the form of a cylinder (FIG. 1G), a brick, a square orrectangular tile (FIG. 1A), a hexagonal tile (FIG. 1B), a circular tile(FIG. 1C), a cupped tile (FIG. 1F), a contoured rectangular tile (FIGS.1D, and 1E), or can be assembled into a pre-matted multi-tileconfiguration mounted on a backing material, such as a polymer film, forcovering contoured or curved portions of a sorting apparatus.

The shape of the tile is not particularly limited and the exposedsurface 10 of the tile can be for example square, rectangle, circular,hexagon, octagon, or any other shape that is flat or contoured, that issuitable for an intended use.

In one embodiment, the average thickness 40 of the tile after firing isless than about 0.60 inches. The other dimensions 50, 60 of the firedtile are not particularly critical and can be sized according to theintended application. In one embodiment, the wear tile has a length 50and a width 60, both ranging from about 0.5 to about 10 inches.

In one embodiment in accordance with the present subject matter, acolored wear tile is provided for inhibiting wear to a surface, the wearbeing associated to contact with a moving material. The colored weartile comprises prior to firing, non-volatile components that comprise atleast 85% Al₂O₃. This wt. % for Al₂O₃ excludes the weight of water andother components that volatilize during drying or firing that are in thecomposition prior to drying and firing. The composition of the weartile, prior to firing, includes Al₂O₃ from at least 75 wt. % of theweight of the volatile and non-volatile components, excluding water. Thecolored wear tile has a color that permeates substantially an entiremass of the colored wear tile. That is, the color permeates the tilefrom the exposed surface 10 to the back surface 20, and between the sidesurfaces 30. The colored wear tile has a Vickers hardness from about 900HV5 to about 1350 HV5. The colored wear tile has a thickness of lessthan about 0.60 inches. The colored wear tile has a lightness of about90 or less measured with a CIE D65 illuminant at 10 degrees.

Color and Lightness

As described herein, the wear tiles have characteristics (at least acolor value and/or lightness value) that are sufficiently different fromrespective characteristics of the desired product and/or the material asa whole, such that an optical sorting apparatus can detect and separatethe wear tile, or portions thereof, from the desired product. The weartile may have other characteristics different from those of the desiredproduct that are not limited to color and lightness, but may encompassother perceptible characteristics such as density, size, reflectivity,infra-red absorption/reflectivity, combinations thereof, etc. Thus thepresent subject matter wear tiles are not limited to having only a colorand lightness value that are different from that of the desired productbut may also possess other properties that are dissimilar to the desiredproduct.

Additionally, the colored wear tiles can have characteristics that aredifferent from the associated material or different from both theassociated material and the desired product. In other words, the coloredwear tile has characteristics that are dissimilar to the desiredproduct, but may or may not also have characteristics that aredissimilar to the undesired product portion. For example the wear tilesand the undesired product may have similar lightness and color, bothbeing sufficiently different from the desired product to allow forseparation therefrom. On the other hand, the wear tiles may have a colorand lightness different from the entirety of the associated material. Ineither case, the colored wear tile, or portions thereof, will beseparated from the desired product by the sorting apparatus.

In accordance with the present subject matter, the color and/orlightness of the tiles contrasts with the desired product, e.g., thetiles may have a different lightness value and/or a different colorvalue on the Hunter Lab scale as compared with the desired product.

In the Hunter Lab scale, (also known as the CIELAB scale and named forthe variables L, a, and b), L measures lightness or luminance and variesfrom 100 for perfect white to zero for black, approximately as the eyewould evaluate it. Where DL=L (wear tile)−L (desired product). If DL (orΔL) is positive, the wear tile is lighter than the desired product. IfDL is negative, the wear tile is darker than the desired product.

The chromaticity dimensions (a and b) give understandable designationsof color. The (a) dimension measures redness when positive, gray whenzero, and greenness when negative. Where Da=a(wear tile)−a(desiredproduct). If Da (or Δa) is positive, the wear tile is redder than thedesired product. If Da is negative, the sample is greener than thedesired product.

The (b) dimension measures yellowness when positive, gray when zero, andblueness when negative. Where Db=b(wear tile)−b(desired product). If Db(or Δb) is positive, the wear tile is yellower than the desired product.If Db is negative, the wear tile is bluer than the desired product.

The Hunter total color difference (DE or ΔE) for any illuminant orobserver is calculated as ΔE=√(ΔL²+Δa²+Δb²). In one embodiment, thetotal color difference (DE) between the tiles and the desired product isabout 10 or more.

In one embodiment of the present subject matter, the tile provides acontrasting lightness values (L) as compared with that of the desiredproduct and providing a lightness value difference (ΔL) between that ofthe tile and that of the desired product as determined by the standardCIELAB scale. In another embodiment, the tile provides contrasting colorvalues (a and b) from that of the desired product. In yet anotherembodiment, the tile provides lightness values, color values, andcombinations thereof to provide contrast from the desired product.

In one embodiment in accordance with the present subject matter, thedifference in lightness values ΔL between the tile and desired producthas an absolute value of greater than about 10. In another embodiment,the absolute value of ΔL is greater than about 20, and in still anotherembodiment greater than about 25. In a particular embodiment, theabsolute value of ΔL is about 30 or higher. The tile used in accordancewith the present subject matter and corresponding L, a, and b values forthose tile are measured with a spectrophotometer.

In accordance with the present subject matter, the wear tiles are suchthat the color and/or lightness value permeates the entire mass of thetile, or at least substantially so. In other words, the color is infusedthroughout the tile body running through the bulk of the tile, ratherthan just on or near one or more surfaces of the tile. In contrast,domestic tiles used for decoration or other similar purposes only have acolor at a surface thereof, wherein a colored glaze is applied atop thetile and fired wherein the color does not substantially penetrate thebody of the tile but rather, is only on a surface thereof.

As the present subject matter tiles are worn, color is always displayedat the exposed surface 10 because the color in the wear tiles runssubstantially throughout the mass of the tiles. In other words, thecolor within the bulk of the wear tile is continually displayed at theexposed surface 10 of the tile 1 as the tile wears away due to exposureand contact with the associated material. For example, if any tile orpiece of a tile happens to chip off and mix with the associatedmaterial, then that portion of the tile will have color and/or lightnessdifferent than the color and/or lightness of the desired product.Because the portion of the tile has color, it will be easily separatedfrom the desired product by the optical sorter. Further, the portion ofthe tile that was underneath the chipped off portion becomes the exposedsurface and will also display the color of the wear tile. In oneembodiment, the color in the wear tile is substantially uniformthroughout the mass of the tile.

In another embodiment, a small color or lightness gradient is presentthrough the mass of the wear tile from one surface to another. In oneaspect, the gradient can transition from one lightness value to another(i.e., change in L value); for example, from a dark shade of a color toa lighter shade of the same color. In another aspect, the gradient cantransition from one color to a different color (i.e. change in a and bvalues). In these gradient aspects, the gradient through the mass of thewear tile can help aid in determining the level of wear experienced bythe wear tile and an indication that the wear tile should be replacedwith a new tile. A combination of these two aspects (i.e. lightness andcolor gradients) is also contemplated. In any event, the gradient valuesof lightness and/or color through the mass of the tile as compared tothe lightness and color of the desired product is such that the opticalsorter can separate the wear tile, or portions thereof, from the desiredproduct.

The wear tiles can be of any color and lightness, as long as the colorand lightness are sufficiently different from that of the desiredproduct to allow optical sorters to separate pieces of the wear tilefrom the desired product. Although not limited to such, in variousembodiments in accordance with the present subject matter the wear tilesare brown, pink, blue or black.

Composition and Preparation

The color and lightness of the colored wear tile is largely affected bythe composition and preparation techniques. Ordinarily, domestic tilescomprise a relatively low level of Al₂O₃ (i.e., under 30 wt. %) and arenot sufficiently hard for use as wear tiles in optical sorters. Incontrast, traditional wear tiles consist essentially of Al₂O₃, whichwhen fired, produces acceptably hard tiles that display shades of white.One problem with such wear tiles is that their various shades of whitecolor makes them unsuitable for use in automated optical sorters used toseparate associated material that also has shades of white color, suchas white rice. Introduction of other ingredients to these white weartiles may impart color, but may also compromise hardness and usefulnessof the tile for use as a wear tile.

In this regard, colored wear tiles in accordance with the presentsubject matter are produced by firing a composition containing prior tofiring non-volatile components comprising at least 85 wt. % Al₂O₃ . Thiswt. % for Al₂O₃ excludes the weight of water and other components thatvolatilize during drying or firing that are in the composition prior todrying or firing. Further, the composition contains prior to firing,Al₂O₃ from at least 75 wt. % of the total weight of the volatile andnon-volatile components and excluding water. The composition is fired toproduce a wear tile having a Vickers hardness from about 900 HV5 toabout 1350 HV5 is produced. A preferred hardness for the colored weartile is a Vickers hardness from about 1100 HV5 to about 1350 HV5. Ahardness of about 900 HV5 to about 1350 HV5 ensures a suitable servicelife for the wear tiles and protection for sorting machines, and isattained by firing the compositions listed herein. Such hardness valuesare not realized in domestic tiles.

The colored wear tile has a thickness of less than about 0.60 inches.The colored wear tile has a lightness of about 90 or less measured witha CIE D65 illuminant at 10 degrees. The colored wear tile has an exposedsurface defined by a shape selected from the group consisting of asquare shape, a rectangle shape, a circular shape, a hexagon shape, andcombinations thereof. Other shapes are also contemplated as part of thepresent subject matter.

In one embodiment, the wear tile is produced by firing a compositioncomprising prior to firing:

-   -   a. Al₂O₃ from about 75 wt. % to about 98 wt. %,    -   b. MnO₂ from about 0.25 wt. % to about 3.5 wt. %,    -   c. TiO₂ from about 0.1 wt. % to about 2.5 wt. %,    -   d. Fe₃O₄ from about 0.1 wt. % to about 2.5 wt. %,    -   e. clay from about 0 wt. % to about 10 wt. %,    -   f. Al₂SiO₅ from about 0.01 wt. % to about 8.0 wt. %,    -   g. talc from about 0 wt. % to about 3.5 wt. %,    -   h. dispersant from about 0 wt. % to about 2.0 wt. %,    -   i. defoamer from about 0 wt. % to about 1.0 wt. %,    -   j. binder from about 0.1 wt. % to about 10 wt. %, and    -   k. calcium stearate from about 0 wt. % to about 4.5 wt. %        In one aspect, firing the composition produces a brown wear        tile.

In another embodiment the colored wear tile is produced by firing acomposition comprising prior to firing:

-   -   a. Al₂O₃ from about 75 wt. % to about 98 wt. %,    -   b. MnO₂ from about 0.5 wt. % to about 2.0 wt. %,    -   c. TiO₂ from about 0.1 wt. % to about 1.5 wt. %,    -   d. Fe₃O₄ from about 0.1 wt. % to about 1.5 wt. %,    -   e. clay from about 1.0 wt. % to about 3.5 wt. %,    -   f. Al₂SiO₅ from about 0.5 wt. % to about 6.0 wt. %,    -   g. talc from about 0.2 wt. % to about 1.5 wt. %,    -   h. dispersant from about 0.2 wt. % to about 0.6 wt. %,    -   i. defoamer from about 0.05 wt. % to about 0.2 wt. %,    -   j. binder from about 0.5 wt. % to about 8.0 wt. %, and    -   k. calcium stearate from about 0.3 wt. % to about 3.5 wt. %        In one aspect, firing the composition produces a brown wear        tile.

In another embodiment the colored wear tile is produced by firing acomposition comprising prior to firing:

-   -   a. Al₂O₃ from about 75 wt. % to about 98 wt. %,    -   b. CaF₂ from about 0.1 wt. % to about 4.0 wt. %,    -   c. Cr₂O₃ from about 0.05 wt. % to about 3.0 wt. %,    -   d. clay from about 0 wt. % to about 4.5 wt. %,    -   e. talc from about 0 wt. % to about 4.0 wt. %,    -   f. tannic acid from about 0 wt. % to about 3.5 wt. %,    -   g. dispersant from about 0 wt. % to about 3.0 wt. %,    -   h. defoamer from about 0 wt. % to about 2.0 wt. %,    -   i. binder from about 0 wt. % to about 10.0 wt. %, and    -   j. calcium stearate from about 0 wt. % to about 4.5 wt. %.        In one aspect, firing the composition produces a pink wear tile.

In another embodiment the colored wear tile is produced by firing acomposition comprising prior to firing:

-   -   a. Al₂O₃ from about 75 wt. % to about 98 wt. %,    -   b. CaF₂ from about 0.5 wt. % to about 3.0 wt. %,    -   c. Cr₂O₃ from about 0.1 wt. % to about 2.0 wt. %,    -   d. clay from about 1.0 wt. % to about 3.5 wt. %,    -   e. talc from about 0.2 wt. % to about 3.0 wt. %,    -   f. tannic acid from about 0.05 wt. % to about 2.0 wt. %,    -   g. dispersant from about 0.2 wt. % to about 1.0 wt. %,    -   h. defoamer from about 0.02 wt. % to about 0.2 wt. %,    -   i. binder from about 0.7 wt. % to about 7.5 wt. %, and    -   j. calcium stearate from about 0.1 wt. % to about 3.5 wt. %.        In one aspect, firing the composition produces a pink wear tile.

In another embodiment the colored wear tile is produced by firing acomposition comprising prior to firing:

-   -   a. Al₂O₃ from about 75 wt. % to about 98 wt. %,    -   b. Al₂SiO₅ from about 0.01 wt. % to about 8.0 wt. %,    -   c. Cr₂O₃ from about 0.05 wt. % to about 3.0 wt. %,    -   d. clay from about 0 wt. % to about 10.0 wt. %,    -   e. talc from about 0 wt. % to about 4.0 wt. %,    -   f. Stonelite (CaMg(CO₃)₂—Fe₂O₃) or dolomite (CaMg(CO₃)₂) from        about 0 wt. % to about 3.5 wt. %,    -   g. dispersant from about 0 wt. % to about 3.0 wt. %,    -   h. defoamer from about 0 wt. % to about 2.0 wt. %,    -   i. binder from about 0 wt. % to about 10.0 wt. %, and    -   j. calcium stearate from about 0 wt. % to about 4.5 wt. %.        In one aspect, firing the composition produces a pink wear tile.

In another embodiment the colored wear tile is produced by firing acomposition comprising prior to firing:

-   -   a. Al₂O₃ from about 75 wt. % to about 98 wt. %,    -   b. TiO₂ from about 0.5 wt. % to about 5.0 wt. %,    -   c. CoO from about 0 wt. % to about 3.0 wt. %,    -   d. Fe₃O₄ from about 0 wt. % to about 3.0 wt. %,    -   e. NiO₂ from about 0 wt. % to about 3.0 wt. %,    -   f. Kaolin clay (Al₂Si₂O₅(OH)₄) from about 1.0 wt. % to about 8.0        wt. %,    -   g. dispersant from about 0 wt. % to about 3.0 wt. %,    -   h. defoamer from about 0 wt. % to about 2.0 wt. %,    -   i. binder from about 0 wt. % to about 5.0 wt. %, and    -   j. calcium stearate from about 0 wt. % to about 3.5 wt. %.        In one aspect, firing the composition produces a black wear        tile.

In another embodiment the colored wear tile is produced by firing acomposition comprising prior to firing:

-   -   a. Al₂O₃ from about 75 wt. % to about 98 wt. %,    -   b. Al₂SiO₅ from about 0.5 wt. % to about 8.0 wt. %,    -   c. clay from about 0 wt. % to about 10.0 wt. %,    -   d. talc from about 0 wt. % to about 4.0 wt. %,    -   e. Stonelite (CaMg(CO₃)₂—Fe₂O₃) or dolomite (CaMg(CO₃)₂) from        about 0 wt. % to about 3.5 wt. %,    -   f. CoO from about 0 wt. % to about 3.0 wt. %,    -   g. dispersant from about 0 wt. % to about 3.0 wt. %,    -   h. defoamer from about 0 wt. % to about 2.0 wt. %,    -   i. binder from about 0 wt. % to about 5.0 wt. %, and    -   j. calcium stearate from about 0 wt. % to about 3.5 wt. %.        In one aspect, firing the composition produces a blue wear tile.

In one aspect white crystalline non-fibrous calcined alumina powder isused as the source for Al₂O₃. A suitable grade of calcined alumina maycontain trace amounts (<0.5%) of SiO₂, Fe₂O₃, Na₂O, and has a loss onignition from 300-1200° C. of about 0.15%. Suitable commerciallyavailable grades of calcined alumina include AC-2 Alumina from AluChem,Inc., Cincinnati, Ohio or GMU-C grade calcined alumina.

In one aspect, the clay used to produce the wear tile comprises ballclay. Ball clay is used for imparting workability, plasticity, andstrength to the mixed composition in drying. Ball clay compriseskaolinite, mica, and quartz and has a chemical formula Al₂O₃-2SiO₂-2H₂Oand having a loss on ignition of about 12%. Ball clay may include otherimpurities such as SiO₂ and TiO₂. One suitable commercially availablegrade of ball clay includes Champion and Challenger (C&C) Ball Clay,supplied by Laguna Clay Company, City of Industry, Calif. In anotheraspect, the clay used to produce the wear tile comprises kaolin clay.Kaolin clay is ceramic kaolin which offers very white fired color, goodforming characteristics, high green strength, and good suspensioncapabilities and cleanliness. Kaolin clay has a chemical formulaAl₂O₃-2SiO₂-2H₂O and has a loss on ignition of about 14%. One suitablecommercially available grade of kaolin clay is Edgar Plastic Kaolin(EPK) clay supplied by Edgar Minerals, Edgar, Fla.

In one aspect, Kyanite is used as the source for Al₂SiO₅.

In one aspect, the talc used to produce the wear tile comprises Americantalc supplied by the American Talc Company, Van Horn, Tex.; or MilwhiteTDM 92 talc supplied by Milwhite Inc., Laredo, Tex.

In one aspect, the dispersant comprises ammonium polyacrylate. Thedispersant is in liquid form and has about 40% solids loading. Theammonium polyacrylate has a molecular weight of about 3500. Thedispersant is used to lower the viscosity and to inhibit settling oragglomeration of particulate solids in the composition and to facilitateadequate dispersion. One suitable commercially available ammoniumpolyacrylate for use as a dispersant is Darvan 821A, supplied byVanderbilt Minerals, LLC, Norwalk, Conn.

In one aspect, the defoamer used in the composition comprises a complexalcohol containing material. One suitable commercially availabledefoamer is Foamaster® A, supplied by Cognis, Monheim, Germany.

In one aspect, the binder used is an aqueous, acrylic emulsion used forenhancing green strength of the wear tiles. A suitable commerciallyavailable grade is Duramax™ B-1022 supplied by Dow Chemical Company,Wilmington, Del. In another aspect, the binder used is a low Tg acrylicaqueous emulsion. A suitable commercially available grade is Duramax™B-1000 also supplied by Dow Chemical Company. In another aspect, thebinder used is a polyvinyl alcohol. One suitable commercially availablegrade is Selvol™ 203 supplied by Sekisui Chemical Company, Ltd. Inanother aspect, the binder used is a polyethylene glycol (“PEG”) havingan average molecular weight of between 4000 daltons (“PEG 4000”) and8000 daltons (“PEG 8000”). In one aspect, PEG with a molecular weight ofabout 4600 (“PEG 4600”) is used.

The compositions can optionally include water or one or more othervehicles. The amount of water present in the slurry may be any amountsuitable to provide uniform distribution and mixing of the components.Other additives may also be added to the composition including tannicacid, fluorspar (CaF₂), other oxides from those mentioned above, such asChrome III Oxide (Cr₂O₃), other binders, pH adjusting agents, sinteringaids, and plasticizers, for example.

Production methods for colored wear tiles in accordance with the presentsubject matter are not particularly limited. Any production method thatsatisfactorily mixes the components is suitable. Generally, thecomponents are combined to form a slurry and the slurry is dried andmilled to form a free flowing powder. The powder is cold or dry pressedto form a green body having a particular shape. The green body is thenfired at high temperatures to remove volatile contents including thebinder, and to sinter the remaining components to form the wear tiles.

Standard drying and firing techniques can be used in accordance with thepresent subject matter.

In one embodiment, the method of production comprises mixing thecomponents in a mill, adding water to the mixed components to form aliquid suspension, spray drying the composition to remove the water,cold pressing the composition into the desired form, and firing the coldpressed composition at or above about 2500° F. from about 45 minutes toabout 90 minutes.

Apparatuses

Optical sorting apparatuses are generally used for sorting foodstuffs,plastics, and other material. One typical sorting apparatus is shown forexample in FIG. 2. It will be understood that the present subject matteris not limited to the apparatus as shown in FIG. 2, but can includeother types of sorting apparatuses with different configurations. Asorting apparatus typically is constructed from stainless steel or othermetal and usually comprises a number of components including a feed ordelivery system 110 for transporting a material 200 to be sorted, and asorting implement or divider 120 to separate the material into desiredproduct 211 and undesired product 212. The feed can comprise materialinput hoppers 111, vibratory feeders/conveyors 112 including a vibrator113, ducting, separators, silos, milling equipment, and chutes. Thesorting implement 120 can comprise an optical system 121 for determiningthe characteristics of the material and/or identifying the at least twogroups. The optical system 121 can include scanners, cameras, and/orsensors for detecting the characteristics of the material; various formsof lighting (including visible, UV, and x-ray) to properly illuminatethe material, and computer controls for processing the information andfor operation of the optical system. The optical system 121 communicateswith an ejector 122 for separating the material into at least twogroups. In one aspect, the ejector 122 is pneumatic and uses a burst ofcompressed air for separating the material. If any of the wear tiles, orportions or pieces thereof, mix with the material during sorting, thesorting implement 120 separates the wear tiles, or portions or piecesthereof, from the desired product based on at least color and/orlightness differences between the wear tile and desired product.

The sorting apparatus 100 can also include one or more receptacles 130for ordering the sorted material 210. Other additional components can beincluded in the apparatus to facilitate the sorting of material.

Many of these components come into contact with the associated materialto be sorted and are subject to wear therefrom, particularly the hopper111, feeder 112, chute 114, and receptacle 130. The components of thesorting apparatus that are subject to wear have typical service lives ofabout a year depending on the operating conditions. In order to extendthese service lives and to save cost on component replacement andmachine down-time associated with repair, wear tiles 1 are applied to atleast portions of such components in order to prevent the associatedmaterial from contacting the covered components. As shown in FIG. 2, thewear tiles 1 are applied to the inside surface of the hopper 111, asurface of the feeder 112, a surface of the chute 114, and an insidesurface of the receptacle 130. In accordance with the present subjectmatter, it will be understood that the wear tiles can be applied to moreor fewer surfaces or portions thereof than that depicted in FIG. 2. Thewear tiles, so applied, are then subject to wear, rather than thecovered surfaces of the components being subject to wear. Worn weartiles can be more easily replaced than entire machine parts and new weartiles are attached when desired.

Colored wear tiles that are used to prevent or inhibit wear on sortingmachines are formed to suitably cover parts that are subject to wear andto prevent the parts from coming into contact with an associatedmaterial. For machine parts that are essentially flat, flat tile can beattached thereto in order to prevent wear to the parts. For parts thatare contoured, tile that is contoured, or flat, can be utilized.

Wear tile can be applied over a machine part as one continuous piece, asoverlapping tiles, as interlocking tiles, as abutted tiles, orcombinations thereof in order to prevent wear. In one embodiment forcurved parts of an apparatus, flat tile are applied that have an exposedsurface 10 defining any shape and having a relatively smaller length 50and width 60 dimension. In this embodiment, the tile has a length andwidth from about 0.5 to about 2.0 inches. These smaller tiles are usefulbecause they can accommodate the curved surfaces of a contoured machinepart. In one aspect, the relatively smaller tiles are pre-matted on awoven polymer backing or other suitable backing for ease of application.Tiles that are abutted, one side surface to another, can additionallyhave grout therebetween to protect the machine parts from wear.

In any case, the colored wear tile has a thickness 40 of about 0.60inches or less in accordance with the present subject matter. Thisthickness ensures that the thickness of the wear tile does not interferewith the operation or material capacity of an optical sorter. Wear tilewith thicknesses of 0.60 inches or less lining portions of the apparatuswill not significantly block or interfere with the delivery system orpathways therein. Wear tile having thicknesses exceeding 0.60 inchestend to decrease the capacity of the sorter. In other words, the amountof material that can be processed by the sorter in a given amount oftime can be reduced because the volume capacity in the hopper 111,feeder 112, chute 114, receptacle 130, and other covered portions isreduced when relatively thicker wear tile is attached thereto. Thus, thepathway for the associated material 200 is constricted with the use ofthicker wear tile.

Colored wear tiles are attached to parts of the sorting apparatus bywelding, adhesive (i.e., epoxy, room-temperature vulcanizing rubber,etc.), mechanical attachment (threaded bolt or screw, tongued andgrooved tile, dovetail grooved tile, compression fitting tile),pre-matted tile, as pre-formed one-piece sections, or other known means,wherein the back surface 20 of the tile 1 is facing the intended part ofthe apparatus 100 to be covered.

Chosen color and/or lightness values for the desired product 211 areestablished for the sorting machine 100 along with an acceptabledifference or range from these preferred values. The sorting apparatusis calibrated to accept material into the desired product portion 211that is within the maximum acceptable difference from the established orpreferred color and/or lightness values. Any portion of the material 200that falls outside, rather than within, the maximum acceptable limitswill be diverted to the undesired product portion 212 as shown in FIG.2. The colored wear tile provides color and/or lightness contrastingsufficiently from the preferred color and/or lightness such that if thecolored wear tile, or portions or pieces thereof, become mixed with thematerial, then the sorting apparatus will separate the colored wear tilefrom the desired product. The colored wear tile has a color and/orlightness that fall outside the maximum acceptable limits establishedfor the desired product and is thus, separated from the desired product211. In one aspect, the colored wear tile is separated into theundesired product 212.

Apparatuses in accordance with the present subject matter utilizecolored wear tiles that have characteristics as described herein; suchdescription being incorporated by reference in the instant apparatuses.

In one embodiment in accordance with the present subject matter, asorting apparatus is provided comprising a feed, an implement, and weartiles. The feed delivers a material to be sorted to the implement. Theimplement sorts the material into at least two groups based on one ormore characteristics of the material including a color parameter, one ofthe at least two groups comprising desired product. The wear tiles covera portion of the sorting apparatus to substantially prevent the materialfrom contacting the covered portion of the sorting apparatus duringsorting. The wear tiles have a color sufficiently different from a colorof the desired product such that the wear tiles, or portions or piecesthereof that may mix with the material, are sorted by the implement fromthe desired product.

In another embodiment in accordance with the present subject matter, anapparatus is provided for separating portions of a material into adesired product portion and an undesired product portion, wherein theseparating is based on perceptible characteristics of the material, oneof the perceptible characteristics being color. The apparatus comprisesa delivery system for transporting the material to be sorted; a dividerfor separating the desired product from the undesired product, andcolored wear tiles covering portions of the apparatus that otherwisewould be subject to wear from coming into contact with the material. Thecolored wear tiles have a color that permeates substantially an entiremass of the colored wear tiles. The color of the colored wear tiles issufficiently different from the color of the material such that thedivider is able to separate the colored wear tiles, or portions orpieces thereof that may mix with the material, from the desired productportion. The delivery system transports the material to the divider, andthe divider separates the material.

In another embodiment, the sorting apparatus includes a receptacle thatorders the sorted material. The receptacle can comprise one or morereceptacles or containers. If only one, then the receptacle has means,such as for example walls or dividers, to keep the sorted materialseparated, for example separated into desired product 211 and undesiredproduct 212 as shown in FIG. 2.

Methods

The present subject matter provides methods related to the use of thecolored wear tile in sorting apparatuses. The methods provide for theseparation of an associated material into a desired product and anundesired product and also provide for colored wear tile, or portions orpieces thereof that may become mixed with the associated material, to beseparated from the desired product based on differences in the colorand/or lightness of the colored wear tile and the desired product. Thedescription of the colored wear tile and the apparatuses elsewhereprovided, is incorporated herein by reference.

In one embodiment, a method is provided for separating a material intoat least two groups based on characteristics of the material, thecharacteristics including a color parameter and a lightness parameter.The method comprises providing the material to be separated. The methodincludes providing a sorting apparatus having a feed, a sortingimplement, and colored wear tiles; wherein the feed transports thematerial to the sorting implement, the sorting implement separates thematerial into at least two groups based on the characteristics of thematerial, the colored wear tiles cover portions of the apparatus tosubstantially prevent the covered portions from coming into contact withthe material, and the colored wear tiles have a color and a lightness.The method also comprises passing the material through the sortingapparatus to separate the material into the at least two groups, one ofthe at least two groups comprising desired product having a color andlightness. The sorting implement separates the colored wear tiles, orportions or pieces thereof that may mix with the material, from thedesired product based on differences between the color and lightness ofthe colored wear tiles and the color and lightness of the desiredproduct.

In another embodiment in accordance with the present subject matter, amethod is provided for protecting one or more surfaces of an opticalsorting apparatus that are subject to wear. The apparatus is configuredto sort a material based on characteristics including color. The wear isassociated with the material contacting the one or more surfaces. Themethod comprises covering the one or more surfaces with colored weartiles so as to substantially prevent the material from contacting theone or more surfaces. The material is sorted into two or more groups,one of the two or more groups comprising desired product having a color,another of the two or more groups comprising undesired product. Thecolored wear tiles have a color that permeates substantially an entiremass of the colored wear tiles, the color of the colored wear tilesbeing different from the color of the desired product. The colored weartiles, or portions or pieces thereof that may mix with the material, areseparated from the desired product by the apparatus on the basis of adifference between the color of the colored wear tiles and the color ofthe desired product.

In another embodiment, the material to be separated is rice, whichcomprises various shades of white. Other materials are also contemplatedas being separated by the apparatuses and methods of the instant subjectmatter.

Many other benefits will no doubt become apparent from futureapplication and development of this technology.

As described hereinabove, the present subject matter solves manyproblems associated with previous strategies, systems and/or devices.However, it will be appreciated that various changes in the details,materials and arrangements of components, which have been hereindescribed and illustrated in order to explain the nature of the presentsubject matter, may be made by those skilled in the art withoutdeparting from the principle and scopes of the claimed subject matter,as expressed in the appended claims.

EXAMPLES

The following examples are illustrative of the present subject matterand should not be construed to limit the scope thereof.

Example 1

A batch of a pre-fired composition according the present subject matterwas developed. The composition provides upon forming and firing, weartile having a brown color suitable for use in an optical sortingapparatus. The components,

-   -   a. 866 lbs. AC-2 calcined alumina (Al₂O₃),    -   b. 10 lbs. maganese dioxide (MnO₂),    -   c. 5 lbs. titantium dioxide (TiO₂),    -   d. 10 lbs. black iron oxide (Fe₃O₄),    -   e. 61 lbs. C&C ball clay,    -   f. 48 lbs. kyanite (Al₂SiO₅),    -   g. 3 lbs. Darvan 821-A,    -   h. 1 lbs. Foamaster A, and    -   i. 47 gallons of water,        were mixed in a mill for 12 hours and 20,020 revolutions to        produce median particle size of 3.0 μm±0.2 measured by a        Sedigraph 5120 particle size analyzer. Thereafter,    -   j. 31.6 lbs Duramax B1022,    -   k. 8.7 lbs. Duramax B1000, and    -   l. 6 lbs. CD202 (calcium stearate),        were added to the mixture and milled for 1 hour and 1,7000        revolutions. The mixture was passed through a screen into a tank        and blunged for 2 hours. The composition was spray dried, then        cold pressed into desired shapes and fired in a kiln at 2500° F.        for 45-90 minutes to produce brown wear tile.

Example 2

A batch of a pre-fired composition according the present subject matterwas developed. The composition provides upon forming and firing, weartile having a pink color suitable for use in an optical sortingapparatus. The components,

-   -   a. 13,838 lbs AC-2 calcined alumina (Al₂O₃),    -   b. 300 lbs. fluorspar (CaF₂),    -   c. 150 lbs. chrome oxide (Cr₂O₃),    -   d. 525 lbs. C&C ball clay,    -   e. 187 lbs. American talc,    -   f. 12 lbs. tannic acid,    -   g. 43 lbs. Darvan 821-A, and    -   h. 7 lbs. Foamaster A,        were mixed in a mill with water for 12 hours and 20,020        revolutions to produce median particle size of 3.0 μm±0.2        measured by a Sedigraph 5120 particle size analyzer. Thereafter,    -   i. 474 lbs. Duramax B1022,    -   j. 130 lbs Duramax B100, and    -   k. 90 lbs. CD202 (calcium stearate),        were added to the mixture and milled for 1 hour and 1,7000        revolutions. The mixture was passed through a screen into a tank        and blunged for 2 hours. The composition was spray dried, then        cold pressed into desired shapes and fired in a kiln at 2500° F.        for 45-90 minutes to produce pink wear tile.

Example 3

A batch of a pre-fired composition according the present subject matterwas developed. The composition provides upon forming and firing, weartile having a pink color suitable for use in an optical sortingapparatus. The components,

-   -   a. 13,838 lbs. AC-2 calcined alumina (Al₂O₃),    -   b. 300 lbs. fluorspar (CaF₂),    -   c. 150 lbs. chrome oxide (Cr₂O₃),    -   d. 525 lbs. C&C ball clay,    -   e. 187 lbs. American talc,    -   f. 12 lbs. tannic acid,    -   g. 63 lbs. Selvol™ 203,    -   h. 43 lbs, Darvan 821-A,    -   i. 7 lbs. Foamaster A,        were mixed in a mill with water for 12 hours and 20,020        revolutions to produce median particle size of 3.0 μm±0.2        measured by a Sedigraph 5120 particle size analyzer. Thereafter,    -   j. 150 lbs. PEG 4000,    -   k. 63 lbs. PEG 8000, and    -   l. 90 lbs. CD202 (calcium stearate),        were added to the mixture and milled for 1 hour and 1,7000        revolutions. The mixture was passed through a screen into a tank        and blunged for 2 hours. The composition was spray dried, then        cold pressed into desired shapes and fired in a kiln at 2500° F.        for 45-90 minutes to produce pink wear tile.

Example 4

A batch of a pre-fired composition according the present subject matterwas developed. The composition provides upon forming and firing, weartile having a brown color suitable for use in an optical sortingapparatus. The components,

-   -   a. 12,825 lbs. AC-2 calcined alumina (Al₂O₃),    -   b. 150 lbs. manganese dioxide (MnO₂),    -   c. 150 lbs. black iron oxide (Fe₃O₄),    -   d. 1,050 lbs. C&C ball clay,    -   e. 450 lbs. American talc,    -   f. 75 lbs. titanium dioxide (TiO₂),    -   g. 300 lbs. Kyanite (Al₂SiO₅),    -   h. 43 lbs, Darvan 821-A,    -   i. 8 lbs. Foamaster A,        were mixed in a mill with water for 12 hours and 20,040        revolutions to produce median particle size of 3.0 μm±0.2        measured by a Sedigraph 5120 particle size analyzer. Thereafter,    -   j. 474 lbs. Duramax B1022,    -   k. 130 lbs. Duramax B100, and    -   l. 90 lbs. CD202 (calcium stearate),        were added to the mixture and milled for 1 hour and 1,7000        revolutions. The mixture was passed through a screen into a tank        and blunged for 2 hours. The composition was spray dried, then        cold pressed into desired shapes and fired in a kiln at 2500° F.        for 45-90 minutes to produce brown wear tile.

Example 5

A batch of a pre-fired composition according the present subject matterwas developed. The composition provides upon forming and firing, weartile having a pink color suitable for use in an optical sortingapparatus. The components,

-   -   a. 12,990 lbs. AC-2 calcined alumina (Al₂O₃),    -   b. 330 lbs. Stonelite (CaMg(CO₃)₂—Fe₂O₃) or microfine dolomite        (CaMg(CO₃)₂,    -   c. 300 lbs. chrome oxide (Cr₂O₃),    -   d. 750 lbs. C&C ball clay,    -   e. 330 lbs. Milwhite TDM 92 talc,    -   f. 600 lbs. Kyanite (Al₂SiO₅),    -   g. 43 lbs, Darvan 821-A,    -   h. 8 lbs. Foamaster A,        were mixed in a mill with water for 20 hours and 16,800        revolutions to produce median particle size of 3.0 μm±0.2        measured by a Sedigraph 5120 particle size analyzer. Thereafter,    -   i. 474 lbs. Duramax B1022,    -   j. 130 lbs. Duramax B100, and    -   k. 90 lbs. CD202 (calcium stearate),        were added to the mixture and milled for 1 hour and 840        revolutions. The mixture was passed through a screen into a tank        and blunged for 2 hours. The composition was spray dried, then        cold pressed into desired shapes and fired in a kiln at 2500° F.        for 45-90 minutes to produce pink wear tile.

Example 6

A batch of a pre-fired composition according the present subject matterwas developed. The composition provides upon forming and firing, weartile having a black color suitable for use in an optical sortingapparatus. The components,

-   -   a. 7,200 lbs. GMU-C grade calcined alumina (Al₂O₃),    -   b. 240 lbs. TiO₂,    -   c. 60.3 lbs. cobalt oxide (CoO),    -   d. 60.3 lbs. black iron oxide (Fe₃O₄),    -   e. 60.3 lbs. black nickel oxide (NiO),    -   f. 397 lbs. EPK clay,    -   g. 27 lbs, Darvan 821-A,    -   h. 4 lbs. Foamaster A,    -   i. a 10% Selvol 203 aqueous solution, wherein 80 lbs. of Selvol        203 dispersant was mixed with 86 gallons of water,        were mixed in a mill with water for 6 hours and 6,720        revolutions to produce median particle size of 3.0 μm±0.2        measured by a Sedigraph 5120 particle size analyzer. Thereafter,    -   j. 80 lbs. PEG 4000 and/or PEG 4600,    -   k. 64 lbs. CD202 (calcium stearate),        were added to the mixture and milled for 1 hour and 840        revolutions. The mixture was passed through a screen into a tank        and blunged for 2 hours. The composition was spray dried, then        cold pressed into desired shapes and fired in a kiln at 2500° F.        for 45-90 minutes to produce a black wear tile.

Example 7

A batch of a pre-fired composition according the present subject matterwas developed. The composition provides upon forming and firing, weartile having a blue color suitable for use in an optical sortingapparatus. The components:

-   -   a. 13,290 lbs. AC-2 calcined alumina (Al₂O₃)    -   b. 530 lbs. Kyanite (Al₂SiO₅),    -   c. 640 lbs. C&C ball clay,    -   d. 270 lbs. Milwhite TDM 92 talc,    -   e. 270 lbs. Stonelite (CaMg(CO₃)₂—Fe₂O₃) or microfine dolomite        (CaMg(CO₃)₂,    -   f. 23 lbs. cobalt oxide (CoO),    -   g. 43 lbs, Darvan 821-A,    -   h. 7 lbs. Foamaster A,    -   i. 63 lbs. Selvol 203,        were mixed in a mill with water for 30 hours and 25,200        revolutions to produce median particle size of 2.8 μm±0.2 μm        measured by a Sedigraph 5120 particle size analyzer. Thereafter,    -   j. 150 lbs. PEG 4000 and/or PEG 4600,    -   k. 63 lbs. PEG 8000,    -   l. 75 lbs. CD202 (calcium stearate),        were added to the mixture and milled for 30 minutes and 722        revolutions. The mixture was passed through a screen into a tank        and blunged for 2 hours. The composition was spray dried, then        cold pressed into desired shapes and fired in a kiln at 2500° F.        for 45-90 minutes to produce a blue wear tile.

The principles, embodiments and modes of operation of the presentsubject matter have been described in the foregoing specification. Thepresent subject matter is not to be construed as being limited to theparticular forms disclosed, since these are to be regarded asillustrative rather than restrictive. Variations and changes may be madeby those skilled in the art without departing from the spirit of thepresent subject matter.

1. A sorting apparatus comprising a feed, an implement, and wear tileswherein: the feed delivers a material to be sorted to the implement, theimplement sorts the material into at least two groups based on one ormore characteristics of the material including a color parameter, one ofthe at least two groups comprising desired product, and the wear tilescover a portion of the sorting apparatus to substantially prevent thematerial from contacting the covered portion of the sorting apparatusduring sorting, the wear tiles having a color sufficiently differentfrom a color of the desired product such that the wear tiles, orportions or pieces thereof, that may mix with the material are sorted bythe implement from the desired product.
 2. The sorting apparatusaccording to claim 1, wherein the color of the wear tiles permeatessubstantially an entire mass of the wear tiles.
 3. The sorting apparatusaccording to claim 2, wherein the wear tiles are produced by firing acomposition at or above about 2500° F. from about 45 minutes to about 90minutes, the composition comprising prior to firing: a. Al₂O₃ from about75 wt. % to about 98 wt. %, b. MnO₂ from about 0.25 wt. % to about 3.5wt. %, c. TiO₂ from about 0.1 wt. % to about 2.5 wt. %, d. Fe₃O₄ fromabout 0.1 wt. % to about 2.5 wt. %, e. clay from about 0 wt. % to about10 wt. %, f. Al₂SiO₅ from about 0.01 wt. % to about 8.0 wt. %, g. talcfrom about 0 wt. % to about 2.5 wt. %, h. dispersant from about 0 wt. %to about 2.0 wt. %, i. defoamer from about 0 wt. % to about 1.0 wt. %,j. binder from about 0.1 wt. % to about 10 wt. %, and k. calciumstearate from about 0 wt. % to about 4.5 wt. %.
 4. The sorting apparatusaccording to claim 3, wherein the composition comprises prior to firing:a. Al₂O₃ from about 75 wt. % to about 98 wt. %, b. MnO₂ from about 0.5wt. % to about 2.0 wt. %, c. TiO₂ from about 0.1 wt. % to about 1.5 wt.%, d. Fe₃O₄ from about 0.1 wt. % to about 1.5 wt. %, e. clay from about1.0 wt. % to about 3.5 wt. %, f. Al₂SiO₅ from about 0.5 wt. % to about6.0 wt. %, g. talc from about 0.2 wt. % to about 1.5 wt. %, h.dispersant from about 0.2 wt. % to about 0.6 wt. %, i. defoamer fromabout 0.05 wt. % to about 0.2 wt. %, j. binder from about 0.5 wt. % toabout 8.0 wt. %, and k. calcium stearate from about 0.3 wt. % to about3.5 wt. %.
 5. The sorting apparatus according to claim 2, wherein thewear tiles are produced by firing a composition at or above about 2500°F. from about 45 minutes to about 90 minutes, the composition comprisingprior to firing: a. Al₂O₃ from about 75 wt. % to about 98 wt. %, b. CaF₂from about 0.1 wt. % to about 4.0 wt. %, c. Cr₂O₃ from about 0.05 wt. %to about 3.0 wt. %, d. clay from about 0 wt. % to about 4.5 wt. %, e.talc from about 0 wt. % to about 4.0 wt. %, f. tannic acid from about 0wt. % to about 3.5 wt. %, g. dispersant from about 0 wt. % to about 3.0wt. %, h. defoamer from about 0 wt. % to about 2.0 wt. %, i. binder fromabout 0 wt. % to about 10.0 wt. %, and j. calcium stearate from about 0wt. % to about 4.5 wt. %.
 6. The sorting apparatus according to claim 5,wherein the composition comprises prior to firing: a. Al₂O₃ from about75 wt. % to about 98 wt. %, b. CaF₂ from about 0.5 wt. % to about 3.0wt. %, c. Cr₂O₃ from about 0.1 wt. % to about 2.0 wt. %, d. clay fromabout 1.0 wt. % to about 3.5 wt. %, e. talc from about 0.2 wt. % toabout 3.0 wt. %, f. tannic acid from about 0.05 wt. % to about 2.0 wt.%, g. dispersant from about 0.2 wt. % to about 1.0 wt. %, h. defoamerfrom about 0.02 wt. % to about 0.2 wt. %, i. binder from about 0.7 wt. %to about 7.5 wt. %, and j. calcium stearate from about 0.1 wt. % toabout 3.5 wt. %.
 7. The sorting apparatus according to claim 2, whereinthe wear tiles are produced by firing a composition at or above about2500° F. from about 45 minutes to about 90 minutes, the compositioncomprising prior to firing: a. Al₂O₃ from about 75 wt. % to about 98 wt.%, b. Al₂SiO₅ from about 0.01 wt. % to about 8.0 wt. %, c. Cr₂O₃ fromabout 0.05 wt. % to about 3.0 wt. %, d. clay from about 0 wt. % to about10.0 wt. %, e. talc from about 0 wt. % to about 4.0 wt. %, f. Stonelite(CaMg(CO₃)₂—Fe₂O₃) or dolomite (CaMg(CO₃)₂) from about 0 wt. % to about3.5 wt. %, g. dispersant from about 0 wt. % to about 3.0 wt. %, h.defoamer from about 0 wt. % to about 2.0 wt. %, i. binder from about 0wt. % to about 10.0 wt. %, and j. calcium stearate from about 0 wt. % toabout 4.5 wt. %.
 8. The sorting apparatus according to claim 2, whereinthe wear tiles are produced by firing a composition at or above about2500° F. from about 45 minutes to about 90 minutes, the compositioncomprising prior to firing: a. Al₂O₃ from about 75 wt. % to about 98 wt.%, b. TiO₂ from about 0.5 wt. % to about 5.0 wt. %, c. CoO from about 0wt. % to about 3.0 wt. %, d. Fe₃O₄ from about 0 wt. % to about 3.0 wt.%, e. NiO₂ from about 0 wt. % to about 3.0 wt. %, f. Kaolin clay(Al₂Si₂O₅(OH)₄) from about 1.0 wt. % to about 8.0 wt. %, g. dispersantfrom about 0 wt. % to about 3.0 wt. %, h. defoamer from about 0 wt. % toabout 2.0 wt. %, i. binder from about 0 wt. % to about 5.0 wt. %, and j.calcium stearate from about 0 wt. % to about 3.5 wt. %.
 9. The sortingapparatus according to claim 2, wherein the wear tiles are produced byfiring a composition at or above about 2500° F. from about 45 minutes toabout 90 minutes, the composition comprising prior to firing: a. Al₂O₃from about 75 wt. % to about 98 wt. %, b. Al₂SiO₅ from about 0.5 wt. %to about 8.0 wt. %, c. clay from about 0 wt. % to about 10.0 wt. %, d.talc from about 0 wt. % to about 4.0 wt. %, e. Stonelite(CaMg(CO₃)₂—Fe₂O₃) or dolomite (CaMg(CO₃)₂) from about 0 wt. % to about3.5 wt. %, f. CoO from about 0 wt. % to about 3.0 wt. %, g. dispersantfrom about 0 wt. % to about 3.0 wt. %, h. defoamer from about 0 wt. % toabout 2.0 wt. %, i. binder from about 0 wt. % to about 5.0 wt. %, and j.calcium stearate from about 0 wt. % to about 3.5 wt. %.
 10. The sortingapparatus according to claim 1, wherein a DE value between the weartiles and the desired product is equal to or greater than
 10. 11. Thesorting apparatus according to claim 1, wherein the wear tiles have alightness that is 90 or less measured with a CIE D65 illuminant at 10degrees.
 12. The sorting apparatus according to claim 1, wherein thewear tiles have an exposed surface defined by a square shape, arectangle shape, a circular shape, or a hexagon shape, and have athickness of less than about 0.60 inches.
 13. The sorting apparatusaccording to claim 1, wherein the wear tiles have a Vickers hardnessfrom about 900 HV5 to about 1350 HV5.
 14. The sorting apparatusaccording to claim 13, wherein the wear tiles have a Vickers hardnessfrom about 1100 HV5 to about 1350 HV5.
 15. The sorting apparatusaccording to claim 1, wherein the wear tiles are mounted to at least aportion of the sorting apparatus by one selected from the groupconsisting of an adhesive, a weld, mechanical attachment means, andcombinations thereof.
 16. The sorting apparatus according to claim 1,wherein: the feed comprises an input hopper, a vibrating conveyor, and achute; and the wear tiles cover at least a portion of the input hopper,at least a portion of the vibrating conveyor, at least a portion of thechute, or combinations thereof.
 17. The sorting apparatus according toclaim 1, wherein the implement comprises: an ejector for separating thematerial into the at least two groups; and an optical system foridentifying the at least two groups; wherein the optical systemcommunicates with the ejector for the sorting of the material and thewear tiles, or portions or pieces thereof, that may mix with thematerial during sorting.
 18. The sorting apparatus according to claim17, wherein the ejector is pneumatic and utilizes a burst of air forseparating.
 19. The sorting apparatus according to claim 1, wherein thematerial comprises rice.
 20. A method for separating a material into atleast two groups based on characteristics of the material, thecharacteristics including a color parameter and a lightness parameter,the method comprising: providing the material to be separated, providinga sorting apparatus comprising a feed, a sorting implement, and coloredwear tiles; wherein the feed transports the material to the sortingimplement, the sorting implement separates the material into at leasttwo groups based on the characteristics of the material, the coloredwear tiles cover portions of the apparatus to substantially prevent thematerial from coming into contact with the covered portions, and thecolored wear tiles have a color and a lightness; and passing thematerial through the sorting apparatus to separate the material into theat least two groups, one of the at least two groups comprising desiredproduct having a color and lightness; wherein the colored wear tiles, orportions or pieces thereof, that may mix with the material are separatedfrom the desired product by the sorting implement based on differencesbetween the color and lightness of the colored wear tiles and the colorand lightness of the desired product.
 21. The method according to claim20, wherein the color of the colored wear tiles permeates substantiallyan entire mass of the colored wear tiles.
 22. The method according toclaim 21, wherein the wear tiles are brown and are produced by firing acomposition at or above about 2500° F. from about 45 minutes to about 90minutes, the composition comprising prior to firing: a. Al₂O₃ from about75 wt. % to about 98 wt. %, b. MnO₂ from about 0.25 wt. % to about 3.5wt. %, c. TiO₂ from about 0.1 wt. % to about 2.5 wt. %, d. Fe₃O₄ fromabout 0.1 wt. % to about 2.5 wt. %, e. clay from about 0 wt. % to about10 wt. %, f. Al₂SiO₅ from about 0.01 wt. % to about 8.0 wt. %, g. talcfrom about 0 wt. % to about 2.5 wt. %, h. dispersant from about 0 wt. %to about 2.0 wt. %, i. defoamer from about 0 wt. % to about 1.0 wt. %,j. binder from about 0.1 wt. % to about 10 wt. %, and k. calciumstearate from about 0 wt. % to about 4.5 wt. %.
 23. The method accordingto claim 22, wherein the composition comprises prior to firing: a. Al₂O₃from about 75 wt. % to about 98 wt. %, b. MnO₂ from about 0.5 wt. % toabout 2.0 wt. %, c. TiO₂ from about 0.1 wt. % to about 1.5 wt. %, d.Fe₃O₄ from about 0.1 wt. % to about 1.5 wt. %, e. clay from about 1.0wt. % to about 3.5 wt. %, f. Al₂SiO₅ from about 0.5 wt. % to about 6.0wt. %, g. talc from about 0.2 wt. % to about 1.5 wt. %, h. dispersantfrom about 0.2 wt. % to about 0.6 wt. %, i. defoamer from about 0.05 wt.% to about 0.2 wt. %, j. binder from about 0.5 wt. % to about 8.0 wt. %,and k. calcium stearate from about 0.3 wt. % to about 3.5 wt. %.
 24. Themethod according to claim 21, wherein the colored wear tiles are pinkand the colored wear tiles are produced by firing a composition at orabove about 2500° F. from about 45 minutes to about 90 minutes, thecomposition comprising prior to firing: a. Al₂O₃ from about 75 wt. % toabout 98 wt. %, b. CaF₂ from about 0.1 wt. % to about 4.0 wt. %, c.Cr₂O₃ from about 0.05 wt. % to about 3.0 wt. %, d. clay from about 0 wt.% to about 4.5 wt. %, e. talc from about 0 wt. % to about 4.0 wt. %, f.tannic acid from about 0 wt. % to about 3.5 wt. %, g. dispersant fromabout 0 wt. % to about 3.0 wt. %, h. defoamer from about 0 wt. % toabout 2.0 wt. %, i. binder from about 0 wt. % to about 10.0 wt. %, andj. calcium stearate from about 0 wt. % to about 4.5 wt. %.
 25. Themethod according to claim 24, wherein the composition comprises prior tofiring: a. Al₂O₃ from about 75 wt. % to about 98 wt. %, b. CaF₂ fromabout 0.5 wt. % to about 3.0 wt. %, c. Cr₂O₃ from about 0.1 wt. % toabout 2.0 wt. %, d. clay from about 1.0 wt. % to about 3.5 wt. %, e.talc from about 0.2 wt. % to about 3.0 wt. %, f. tannic acid from about0.05 wt. % to about 2.0 wt. %, g. dispersant from about 0.2 wt. % toabout 1.0 wt. %, h. defoamer from about 0.02 wt. % to about 0.2 wt. %,i. binder from about 0.7 wt. % to about 7.5 wt. %, and j. calciumstearate from about 0.1 wt. % to about 3.5 wt. %.
 26. The methodaccording to claim 21, wherein the colored wear tiles are pink and thecolored wear tiles are produced by firing a composition at or aboveabout 2500° F. from about 45 minutes to about 90 minutes, thecomposition comprising prior to firing: a. Al₂O₃ from about 75 wt. % toabout 98 wt. %, b. Al₂SiO₅ from about 0.01 wt. % to about 8.0 wt. %, c.Cr₂O₃ from about 0.05 wt. % to about 3.0 wt. %, d. clay from about 0 wt.% to about 10.0 wt. %, e. talc from about 0 wt. % to about 4.0 wt. %, f.Stonelite (CaMg(CO₃)₂—Fe₂O₃) or dolomite (CaMg(CO₃)₂) from about 0 wt. %to about 3.5 wt. %, g. dispersant from about 0 wt. % to about 3.0 wt. %,h. defoamer from about 0 wt. % to about 2.0 wt. %, i. binder from about0 wt. % to about 10.0 wt. %, and j. calcium stearate from about 0 wt. %to about 4.5 wt. %.
 27. The method according to claim 21, wherein thecolored wear tiles are blue and the colored wear tiles are produced byfiring a composition at or above about 2500° F. from about 45 minutes toabout 90 minutes, the composition comprising prior to firing: a. Al₂O₃from about 75 wt. % to about 98 wt. %, b. Al₂SiO₅ from about 0.5 wt. %to about 8.0 wt. %, c. clay from about 0 wt. % to about 10.0 wt. %, d.talc from about 0 wt. % to about 4.0 wt. %, e. Stonelite(CaMg(CO₃)₂—Fe₂O₃) or dolomite (CaMg(CO₃)₂) from about 0 wt. % to about3.5 wt. %, f. CoO from about 0 wt. % to about 3.0 wt. %, g. dispersantfrom about 0 wt. % to about 3.0 wt. %, h. defoamer from about 0 wt. % toabout 2.0 wt. %, i. binder from about 0 wt. % to about 5.0 wt. %, and j.calcium stearate from about 0 wt. % to about 3.5 wt. %.
 28. The methodaccording to claim 21, wherein the colored wear tiles are black and thecolored wear tiles are produced by firing a composition at or aboveabout 2500° F. from about 45 minutes to about 90 minutes, thecomposition comprising prior to firing: a. Al₂O₃ from about 75 wt. % toabout 98 wt. %, b. TiO₂ from about 0.5 wt. % to about 5.0 wt. %, c. CoOfrom about 0 wt. % to about 3.0 wt. %, d. Fe₃O₄ from about 0 wt. % toabout 3.0 wt. %, e. NiO₂ from about 0 wt. % to about 3.0 wt. %, f.Kaolin clay (Al₂Si₂O₅(OH)₄) from about 1.0 wt. % to about 8.0 wt. %, g.dispersant from about 0 wt. % to about 3.0 wt. %, h. defoamer from about0 wt. % to about 2.0 wt. %, i. binder from about 0 wt. % to about 5.0wt. %, and j. calcium stearate from about 0 wt. % to about 3.5 wt. %.29. The method according to claim 20, wherein a DE value between thecolored wear tiles and the desired product is equal to or greater than10.
 30. The method according to claim 20, wherein the colored wear tileshave a lightness of 90 or less measured with a CIE D65 illuminant at 10degrees.
 31. The method according to claim 20, wherein the colored weartiles have an exposed surface defined by a square shape, a rectangleshape, a circular shape, or a hexagon shape, and have a thickness ofless than about 0.60 inches.
 32. The method according to claim 20,wherein the colored wear tiles have a Vickers hardness from about 900HV5 to about 1350 HV5.
 33. The method according to claim 32, wherein thecolored wear tiles have a Vickers hardness from about 1100 HV5 to about1350 HV5.
 34. An apparatus for separating portions of a material into adesired product portion and an undesired product portion, wherein theseparating is based on perceptible characteristics of the material, oneof the perceptible characteristics being color, the apparatuscomprising: a delivery system for transporting the material to besorted; a divider for separating the desired product from the undesiredproduct, and colored wear tiles covering portions of the apparatus thatotherwise would be susceptible to wear from coming into contact with thematerial if not covered by the wear tiles, the colored wear tiles havinga color that permeates substantially an entire mass of the colored weartiles, the color of the colored wear tiles being sufficiently differentfrom the color of the desired product portion such that the divider isable to separate the colored wear tiles, or portions or pieces thereofthat may mix with the material, from the desired product portion;wherein the delivery system transports the material to the divider, andthe divider separates the material.
 35. The apparatus according to claim34, wherein the colored wear tiles are brown and the colored wear tilesare produced by firing a composition at or above about 2500° F. fromabout 45 minutes to about 90 minutes, the composition comprising priorto firing: a. Al₂O₃ from about 75 wt. % to about 98 wt. %, b. MnO₂ fromabout 0.25 wt. % to about 3.5 wt. %, c. TiO₂ from about 0.1 wt. % toabout 2.5 wt. %, d. Fe₃O₄ from about 0.1 wt. % to about 2.5 wt. %, e.clay from about 0 wt. % to about 10 wt. %, f. Al₂SiO₅ from about 0.01wt. % to about 8.0 wt. %, g. talc from about 0 wt. % to about 2.5 wt. %,h. dispersant from about 0 wt. % to about 2.0 wt. %, i. defoamer fromabout 0 wt. % to about 1.0 wt. %, j. binder from about 0.1 wt. % toabout 10 wt. %, and k. calcium stearate from about 0 wt. % to about 4.5wt. %.
 36. The apparatus according to claim 35, wherein the compositioncomprises prior to firing: a. Al₂O₃ from about 75 wt. % to about 98 wt.%, b. MnO₂ from about 0.5 wt. % to about 2.0 wt. %, c. TiO₂ from about0.1 wt. % to about 1.5 wt. %, d. Fe₃O₄ from about 0.1 wt. % to about 1.5wt. %, e. clay from about 1.0 wt. % to about 3.5 wt. %, f. Al₂SiO₅ fromabout 0.5 wt. % to about 6.0 wt. %, g. talc from about 0.2 wt. % toabout 1.5 wt. %, h. dispersant from about 0.2 wt. % to about 0.6 wt. %,i. defoamer from about 0.05 wt. % to about 0.2 wt. %, j. binder fromabout 0.5 wt. % to about 8.0 wt. %, and k. calcium stearate from about0.3 wt. % to about 3.5 wt. %.
 37. The apparatus according to claim 34,wherein the colored wear tiles are pink and the colored wear tiles areproduced by firing a composition at or above about 2500° F. from about45 minutes to about 90 minutes, the composition comprising prior tofiring: a. Al₂O₃ from about 75 wt. % to about 98 wt. %, b. CaF₂ fromabout 0.1 wt. % to about 4.0 wt. %, c. Cr₂O₃ from about 0.05 wt. % toabout 3.0 wt. %, d. clay from about 0 wt. % to about 4.5 wt. %, e. talcfrom about 0 wt. % to about 4.0 wt. %, f. tannic acid from about 0 wt. %to about 3.5 wt. %, g. dispersant from about 0 wt. % to about 3.0 wt. %,h. defoamer from about 0 wt. % to about 2.0 wt. %, i. binder from about0 wt. % to about 10.0 wt. %, and j. calcium stearate from about 0 wt. %to about 4.5 wt. %.
 38. The apparatus according to claim 37, wherein thecomposition comprises prior to firing: a. Al₂O₃ from about 75 wt. % toabout 98 wt. %, b. CaF₂ from about 0.5 wt. % to about 3.0 wt. %, c.Cr₂O₃ from about 0.1 wt. % to about 2.0 wt. %, d. clay from about 1.0wt. % to about 3.5 wt. %, e. talc from about 0.2 wt. % to about 3.0 wt.%, f. tannic acid from about 0.05 wt. % to about 2.0 wt. %, g.dispersant from about 0.2 wt. % to about 1.0 wt. %, h. defoamer fromabout 0.02 wt. % to about 0.2 wt. %, i. binder from about 0.7 wt. % toabout 7.5 wt. %, and j. calcium stearate from about 0.1 wt. % to about3.5 wt. %.
 39. The apparatus according to claim 34, wherein the coloredwear tiles are pink and the colored wear tiles are produced by firing acomposition at or above about 2500° F. from about 45 minutes to about 90minutes, the composition comprising prior to firing: a. Al₂O₃ from about75 wt. % to about 98 wt. %, b. Al₂SiO₅ from about 0.01 wt. % to about8.0 wt. %, c. Cr₂O₃ from about 0.05 wt. % to about 3.0 wt. %, d. clayfrom about 0 wt. % to about 10.0 wt. %, e. talc from about 0 wt. % toabout 4.0 wt. %, f. Stonelite (CaMg(CO₃)₂—Fe₂O₃) or dolomite(CaMg(CO₃)₂) from about 0 wt. % to about 3.5 wt. %, g. dispersant fromabout 0 wt. % to about 3.0 wt. %, h. defoamer from about 0 wt. % toabout 2.0 wt. %, i. binder from about 0 wt. % to about 10.0 wt. %, andj. calcium stearate from about 0 wt. % to about 4.5 wt. %.
 40. Theapparatus according to claim 34, wherein the colored wear tiles are blueand the colored wear tiles are produced by firing a composition at orabove about 2500° F. from about 45 minutes to about 90 minutes, thecomposition comprising prior to firing: a. Al₂O₃ from about 75 wt. % toabout 98 wt. %, b. Al₂SiO₅ from about 0.5 wt. % to about 8.0 wt. %, c.clay from about 0 wt. % to about 10.0 wt. %, d. talc from about 0 wt. %to about 4.0 wt. %, e. Stonelite (CaMg(CO₃)₂—Fe₂O₃) or dolomite(CaMg(CO₃)₂) from about 0 wt. % to about 3.5 wt. %, f. CoO from about 0wt. % to about 3.0 wt. %, g. dispersant from about 0 wt. % to about 3.0wt. %, h. defoamer from about 0 wt. % to about 2.0 wt. %, i. binder fromabout 0 wt. % to about 5.0 wt. %, and j. calcium stearate from about 0wt. % to about 3.5 wt. %.
 41. The apparatus according to claim 34,wherein the colored wear tiles are black and the colored wear tiles areproduced by firing a composition at or above about 2500° F. from about45 minutes to about 90 minutes, the composition comprising prior tofiring: a. Al₂O₃ from about 75 wt. % to about 98 wt. %, b. TiO₂ fromabout 0.5 wt. % to about 5.0 wt. %, c. CoO from about 0 wt. % to about3.0 wt. %, d. Fe₃O₄ from about 0 wt. % to about 3.0 wt. %, e. NiO₂ fromabout 0 wt. % to about 3.0 wt. %, f. Kaolin clay (Al₂Si₂O₅(OH)₄) fromabout 1.0 wt. % to about 8.0 wt. %, g. dispersant from about 0 wt. % toabout 3.0 wt. %, h. defoamer from about 0 wt. % to about 2.0 wt. %, i.binder from about 0 wt. % to about 5.0 wt. %, and j. calcium stearatefrom about 0 wt. % to about 3.5 wt. %.
 42. The apparatus according toclaim 34, wherein: the colored wear tiles comprise prior to firing,non-volatile components comprising at least 85 wt. % Al₂O₃, the coloredwear tiles have an exposed surface defined by a square shape, arectangle shape, a circular shape, or a hexagon shape; the colored wearties have a thickness of less than about 0.60 inches; the colored weartiles have a lightness that is 90 or less measured with a CIE D65illuminant at 10 degrees; a DE value between the colored wear tiles andthe desired product portion is equal to or greater than 10; and thecolored wear tiles have a Vickers hardness from about 900 HV5 to about1350 HV5. 43-59. (canceled)
 60. The sorting apparatus according to claim1, further comprising a receptacle for ordering sorted material, whereinthe implement sorts the material into the receptacle.